Lamellar corneal surgery has undergone a steady evolution over the last 50 years. Advancements in the technology, such as automated keratomes and non-freeze, no-suture techniques have markedly improved safety and effectiveness. During the surface ablation craze of the late 80's, Dr. Gholam Peyman, known for his pioneering retina work, realized the utility of preserving all layers of the cornea but taking advantage of the extreme accuracy of the excimer laser. He patented the method for LASIK years ago and studied this technique in his laboratory. He used a YAG laser due to the limited response and acceptance for this technique by the major excimer laser manufacturers. During the years of epikeratoplasty others such as Drs. Lee Nordan and Stephen Slade, as well as Dr. Casimir Swinger, were learning and developing freeze myopic keratomileusis for high myopia. By the late 80's, Dr. Slade was one of a hand full of surgeons still performing this demanding technique. When Dr. Luis Ruiz introduced the automated keratome and the in situ non-freeze, no-suture technique to the lamellar bed, Dr. Slade embraced this and has since introduced this technique to thousands of surgeons worldwide. Although a significant advancement, even Dr. Luis Ruin realized the relative imprecision of making a refractive pass with the keratome. He quickly learned to utilize the excimer laser to precisely reshape the cornea underneath the lamellar corneal flap. The precision achieved has been unparalleled, especially for the moderate to higher myopes.
Worldwide there have been many other surgeons that deserve credit for pursuing the combination of excimer laser with lamellar surgery, most notably Dr. Lucio Buratto of Milan, Italy, and Dr. Ioannis Pallikaris of Greece. The original Buratto technique, however, required cutting a very thick cap and ablating its under surface. Many of these lenticules required suturing, thus required extreme surgical precision and irregular astigmatism rates were quite high. Pallikaris' early work was done on animal models and provided the first histopathology of excimer laser to a lamellar bed. The early Summit excimer laser studies that evaluated the use of lamellar surgery were conducted by Brink, et al.; however, there was a significant loss of best corrected visual acuity and a wide range of outcomes as new surgeons attempted to perform the original suture dependent Burrato technique.
As surgeons began doing lamellar surgery, they became concerned about the potential for inducing irregular astigmatism as well as introducing debris such as epithelial inclusions in the interface. Fortunately, with the introduction of the automated keratome and non-freeze, non-suture techniques, irregular astigmatism rates are reduced. Debris in the interface, however, continues to be a chronic problem. Many surgeons have resorted to never wearing gloves during lamellar surgery just for that reason. Although infections in lamellar surgery are quite low, when you are the patient that has the infection, percentages do not matter. At present, it is unclear whether or not wearing gloves during lamellar surgery is the standard of care. Thus, we need a way to perform lamellar surgery with gloves safely so as not to introduce debris into the interface.
Recently a very famous clinical researcher in excimer laser technology expressed that his job is now to make surface ablation PRK as good or better than LASIK. Preserving all the layers of the cornea provides quicker visual recovery and the predictability is less dependent upon the ablation characteristics of the laser. Thus, LASIK in its infancy already has a head start over any surface ablation technique. Secondly, PRK retreatment is not predictable, LASIK enhancement is possible. The tremendous amounts of research and development required to create the perfect surface ablation could be better spent in perfecting LASIK for all ranges of refractive errors.
There is a growing need to introduce lamellar surgery skills to surgeons new to this arena. Surgeons who have been performing ALK will be prepared to make an easy transition to LASIK. Many of the surgeons making the transition from PRK to LASIK appear totally consumed in what type of ablation to use in the bed, when in reality their primary concerns should be a safe keratectomy and repositioning the cap/flap so that there is the least likely chance for debris in the interface or irregular astigmatism. If that can be reproduced, then enhancement is possible and predictability of the ablation for each surgeon will increase with experience.
Therefore, notwithstanding developments in lamellar surgery to date, techniques and instrumentation are needed to positively impact all lamellar surgeons who have grappled with sight-threatening irregular astigmatism and debris in the interface.